Morocco is the first country producer of phosphate in the world with a real potential of contamination of the environment and individuals there living by fluorine either by phosphate deposits (hydrotelluric fluorosis) and phosphate manufacturing plants (industrial fluorosis). This survey was achieved on 86 dromedaries in a region of the Sahara (Boujdour and Laâyoune) characterized by the presence of phosphate. In addition, blood, soil, water and plant samples were collected for the dosage of fluorine that has been achieved by potentiometric method. The mean fluorine content was below 0.47 ppm, 513 ppm and 4.8 ppm in water, soil and plants respectively. The provinces of Boujdour and Laâyoune are unscathed zones opposite the sources of fluorine contamination, as water, vegetation and soil. The mean plasma fluorine concentration was below 0.06 ppm, thus, the camels of these regions seem therefore also free of fluorine chronic intoxication. However the increased values of fluorine levels in the soil, vegetables, and the plasma of camels in the region of Boujdour can let suppose that this area is close to a source of fluorine contamination. Indeed, the province of Boujdour is located unless 200 km of Boukraa where is situated a processing plant of phosphates. Thus, according orientation and the strength of the present dominant winds in the region of Boujdour, we can give out the hypothesis that by winds are brought in the region of Boujdour of the fluorine particles coming from the region of Boukraa. These winds carrying particles of fluorine eliminated by the factory and also by the extraction of soil particles by erosion. This hypothesis can be verified by a survey establishing a gradient of pollution by fluorine cleared by the deposit or the processing plant of the phosphates considering the direction and the strength of the dominant winds in these regions. (Résumé d'auteur)

In the desert, camel rearing is an important cultural fact. In the present paper, 240 Arabian camels from Emirates were sampled for the determination of trace elements and different heavy metals. The following elements were tested: copper, zinc, iron, aluminium, arsenic, boron, barium, cobalt, chromium, cadmium, manganese, molybdenum, nickel, selenium, strontium and lead. The variation factors included age, sex and physiological status. On the average, the mineral contents were 190.3 µg/100 ml (iron), 60.1 µg/100 ml (copper), 44.0 µg/100 ml (strontium), 22.5 µg/100 ml (arsenic), 20.0 µg/100 ml (zinc), 19.7 µg/100 ml (selenium), 19.3 µg/100 ml (boron) and 14.6 µg/100 ml (barium). Other minerals like aluminium (3.7 µg/100 ml), molybdenum (2.9 µg/100 ml), chromium (2.0 µg/100 ml), nickel (1.8 µg/100 ml), lead (1.5 µg/100 ml), manganese (0.16 µg/100 ml), cobalt (0.08 µg/100 ml) and cadmium (0.07 µg/100 ml) were in very small concentration. Age, sex and physiological effects were assessed for some parameters. According to the lack of references in camel species, it is difficult to link those results to polluting context. But those data could contribute to understand the heavy metal status in camel confronted to pollution. (Résumé d'auteur)

Early interest in selenium by nutritionists was first identified in the 1930 s as a toxic element, nowadays it is known to be important in livestock and human diet. Its poisonous nature arouses the curiosity of researchers to investigate the impact of this element in human and animal metabolism. However, selenium has become the center of attention due to its physiological functions explained on the basis of its role as an active component of the enzyme glutathione peroxidase (GSH-PX), which is responsible for the animal antioxidant defense by destruction of hydrogen peroxide and lipid peroxides. Selenium metabolism and toxicity has been consistently studied in different species but data investigations on camelidae species are very limited. Our current study is configured to investigate the selenium intolerance in dromedary camel and carry out the symptoms related to continuous selenium supplementation. Investigations showed that camel is potentially sensitive to selenium excess. Several symptoms revealed by their different intensity from 3 batches, resumed in alopecia - abnormal movement and posture, breathing difficulties, prostration, diarrhea, lost of weight and nervous alteration. (Résumé d'auteur)

In four regions of Kazakhstan (Atyrau, Aralsk, Shymkent and Almaty), a survey on camel farms was achieved in order to study the variability of the physico-chemical composition of camel milk both in dromedary (Camelus dromedarius) and Bactrian (Camelus bactrianus) camel as well as their hybrids. As the whole, 163 milk samples were analyzed for calcium, phosphorus and iron determination. In order to maximize the variance, the samples were done in four different seasons which expressed the feeding change and the physiological stage changes as the calving season was concentrated in few months. The mean values were respectively 1.232 ± 0.292 g/l, 1.003 ± 0.217 g/l and 2.02 ± 1.24 mg/l for calcium, phosphorus and iron. No species, season or region effect was observed on iron content in the milk. Calcium and phosphorus change significantly according to season and species, but only phosphorus was linked to region effect. Especially phosphorus content is high in Aralsk region (1.156 ± 0.279 g/l). Globally, it is noticeable to observe the high level of phosphorus in the camel milk of Kazakhstan compared to the literature's results. (Résumé d'auteur)